---
title: Sui On-Chain Signatures Verification in Move
---

Move contracts in Sui support verifications for several signature schemes on-chain. Not all signatures supported in on-chain verification are supported as user signature verification. See [Sui Signatures](/concepts/cryptography/transaction-auth/signatures.mdx#user-signature) for valid signature schemes for transaction authorization.

This topic covers:
1. How to use [fastcrypto](https://github.com/MystenLabs/fastcrypto)'s CLI tool to create a signature of a given scheme. For testing and debugging only, DO NOT use in production.
1. Call the Move method on-chain to verification by submitting the signature, the message and the public key. 

Signature schemes covered: 
- Ed25519 signature (64 bytes)
- Secp256k1 non-recoverable signature (64 bytes)
- Secp256k1 recoverable signature (65 bytes)
- Secp256r1 non-recoverable signature (64 bytes)
- Secp256r1 recoverable signature (65 bytes)
- BLS G1 signature (minSig setting)
- BLS G2 signature (minPk setting)

## Usage

### Set up fastcrypto CLI binary

```shell
git@github.com:MystenLabs/fastcrypto.git
cd fastcrypto/
cargo build --bin sigs-cli
```

### Sign with CLI and submit to on-chain Move method

#### Ed25519 signature (64 bytes)

1. Generate a key and sign a message. 

```shell
target/debug/sigs-cli keygen --scheme ed25519 --seed 0000000000000000000000000000000000000000000000000000000000000000                
Private key in hex: $SK
Public key in hex: $PK

target/debug/sigs-cli sign --scheme ed25519 --msg $MSG --secret-key  $SK

Signature in hex: $SIG
Public key in hex: $PK
```

2. Call the verify method in Move. All inputs are represented in bytes in hex format:

```move
    use sui::ed25519;

    let msg = x"$MSG";
    let pk = x"$PK";
    let sig = x"$SIG";
    let verify = ed25519::ed25519_verify(&sig, &pk, &msg);
    assert!(verify == true, 0);
```

#### Secp256k1 non-recoverable signature (64 bytes)

1. Generate a key and sign a message. 

```shell
target/debug/sigs-cli keygen --scheme secp256k1 --seed 0000000000000000000000000000000000000000000000000000000000000000                
Private key in hex: $SK
Public key in hex: $PK

target/debug/sigs-cli sign --scheme secp256k1 --msg $MSG --secret-key $SK

Signature in hex: $SIG
Public key in hex: $PK
```

2. Call the verify method in Move.

```move
    use sui::ecdsa_k1;
    
    let msg = x"$MSG";
    let pk = x"$PK";
    let sig = x"$SIG";
    // The last param 1 represents the hash function used is SHA256, the default hash function used when signing in CLI.
    let verify = ecdsa_k1::secp256k1_verify(&sig, &pk, &msg, 1);
    assert!(verify == true, 0);
```

#### Secp256k1 recoverable signature (65 bytes)

1. Generate a key and sign a message. 

```shell
target/debug/sigs-cli keygen --scheme secp256k1-rec --seed 0000000000000000000000000000000000000000000000000000000000000000                
Private key in hex: $SK
Public key in hex: $PK

target/debug/sigs-cli sign --scheme secp256k1-rec --msg $MSG --secret-key $SK

Signature in hex: $SIG
Public key in hex: $PK
```

2. Call the ecrecover method in Move and check equality.
```move
    use sui::ecdsa_k1;

    let msg = x"$MSG";
    let pk = x"$PK";
    let sig = x"$SIG";
    // The last param 1 represents the hash function used is SHA256, the default hash function used when signing in CLI.
    let recovered = ecdsa_k1::secp256k1_ecrecover(&sig, &msg, 1);
    assert!(pk == recovered, 0);
```

#### Secp256r1 non-recoverable signature (64 bytes)

1. Generate a key and sign a message. 

```shell
target/debug/sigs-cli keygen --scheme secp256r1 --seed 0000000000000000000000000000000000000000000000000000000000000000                
Private key in hex: $SK
Public key in hex: $PK

target/debug/sigs-cli sign --scheme secp256r1 --msg $MSG --secret-key $SK

Signature in hex: $SIG
Public key in hex: $PK
```

2. Call the verify method in Move.

```move
    use sui::ecdsa_r1;

    let msg = x"$MSG";
    let pk = x"$PK";
    let sig = x"$SIG";
    // The last param 1 represents the hash function used is SHA256, the default hash function used when signing in CLI.
    let verify = ecdsa_r1::secp256r1_verify(&sig, &pk, &msg, 1);
    assert!(verify == true, 0);
```

#### Secp256r1 recoverable signature (65 bytes)

1. Generate a key and sign a message. 

```shell
target/debug/sigs-cli keygen --scheme secp256r1-rec --seed 0000000000000000000000000000000000000000000000000000000000000000                
Private key in hex: $SK
Public key in hex: $PK

target/debug/sigs-cli sign --scheme secp256r1-rec --msg $MSG --secret-key $SK

Signature in hex: $SIG
Public key in hex: $PK
```

2. Call the ecrecover method in Move and check equality.

```move
    use sui::ecdsa_r1;

    let msg = x"$MSG";
    let pk = x"$PK";
    let sig = x"$SIG";
    // The last param 1 represents the hash function used is SHA256, the default hash function used when signing in CLI.
    let recovered = ecdsa_r1::secp256r1_ecrecover(&sig, &msg, 1);
    assert!(pk == recovered, 0);
```

#### BLS G1 signature (48 bytes, minSig setting)

1. Generate a key and sign a message. 

```shell
target/debug/sigs-cli keygen --scheme bls12381-minsig --seed 0000000000000000000000000000000000000000000000000000000000000000                
Private key in hex: $SK
Public key in hex: $PK

target/debug/sigs-cli sign --scheme bls12381-minsig --msg $MSG --secret-key $SK

Signature in hex: $SIG
Public key in hex: $PK
```

2. Call the verify method in Move.

```move
    use sui::bls12381;

    let msg = x"$MSG";
    let pk = x"$PK";
    let sig = x"$SIG";
    let verified = bls12381::bls12381_min_sig_verify(&sig, &pk, &msg);
    assert!(verified == true, 0);
```

#### BLS G1 signature (96 bytes, minPk setting)

1. Generate a key and sign a message. 

```shell
target/debug/sigs-cli keygen --scheme bls12381-minpk --seed 0000000000000000000000000000000000000000000000000000000000000000                
Private key in hex: $SK
Public key in hex: $PK

target/debug/sigs-cli sign --scheme bls12381-minpk --msg $MSG --secret-key $SK

Signature in hex: $SIG
Public key in hex: $PK
```

2. Call the verify method in Move.

```move
    use sui::bls12381;

    let msg = x"$MSG";
    let pk = x"$PK";
    let sig = x"$SIG";
    let verified = bls12381::bls12381_min_pk_verify(&sig, &pk, &msg);
    assert!(verified == true, 0);
```
